Sick sinus syndrome

Electronic pacemakers have been used in patients with heart rhythm disorders for device-supported pacing. While effective, there are such shortcomings as limited battery life, permanent implantation of catheters, the lack of autonomic neurohumoral responses, and risks of lead dislodging. Here we describe protocols for establishing porcine models of sick sinus syndrome and complete heart block, and the generation of bioartificial pacemaker by delivering a strategically engineered form of hyperpolarization-activated cyclic nucleotide-gated pacemaker channel protein via somatic gene transfer to convert atrial or ventricular muscle cardiomyocytes into nodal-like cells that rhythmically fire action potentials...

RESEARCH OBJECTIVE: Assessment of sinoatrial node function after Maze III procedure combined with a mitral valve operation. METHODS: 100 patients were included in the research with persistent and long-standing persistent forms of atrial fibrillation (AF) and need of operative treatment concerning valve disease. The following preoperative preparation methods were executed to all patients: Electrocardiogram in 12 standard assignments;Two-dimensional echocardiographic with assessment of systolic and diastolic functions of the left ventricle, size of the left atrium and grade of valve disease;Transesophageal echocardiography for exclusion of blood clots in the left atrium and left atrial appendage;Coronary angiography for exclusion of coronary heart disease;Computer tomography for examination of cardiac chambers and anatomic characteristics of pulmonary veins...

Venous thrombosis after pacemaker implant is a known, although often underrecognized condition that can challenge system revision or upgrading, leading occasionally to thromboembolic complications. Several factors are considered to promote thrombus formation. Among them, alteration of blood flow mechanics due to the presence of catheters in the vessel lumen may itself play a pivotal role. Hereby we present the case of a 65-year old men who underwent a dual-chamber pacemaker implant in another institute for sick sinus syndrome by means of left cephalic venous access...

Resume In accordance with modern concepts, one of the leading roles in the development of paroxysmal atrial fibrillation and flutter, belongs - the restructuring of the myocardium, in second place - sick sinus syndrome and in third place - the presence of accessory pathways and hormonal disorders. The development of atrial fibrillation and flutter in the structural pathology, primarily begins with of drugs if it does not work, we have to carry out ablation. Providing proper, effective and important combination therapy - is the main challenge in cardiology...

The sinoatrial node (SAN) is the dominant pacemaker of the heart. Abnormalities in SAN formation and function can cause sinus arrhythmia, including sick sinus syndrome and sudden death. A better understanding of genes and signaling pathways that regulate SAN development and function is essential to develop more effective treatment to sinus arrhythmia, including biological pacemakers. In this review, we briefly summarize the key processes of SAN morphogenesis during development, and focus on the transcriptional network that drives SAN development...

Cluster headache (CH) is a primary headache disorder with relatively effective treatments. Although few sufficiently controlled trials are available, verapamil is recommended as the first-line prophylactic drug for CH by the French Headache Society (with a low level of evidence, level B) and by the EFNS (European Federation of Neurological Societies, level A). Daily doses of more than 480 mg (and up to 1200 mg daily) are frequently used off-label, while 360 mg daily is the only dosage to have demonstrated its effectiveness in a double-blind trial against placebo, and the usual label posology used by cardiologists is 240 mg daily in hypertension...

AIMS: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in man, causing substantial morbidity and mortality with a major worldwide public health impact. It is increasingly recognized as a highly heritable condition. This study aimed to determine genetic risk factors for early-onset AF. METHODS AND RESULTS: We sequenced the whole genomes of 8453 Icelanders and imputed genotypes of the 25.5 million sequence variants we discovered into 1799 Icelanders with early-onset AF (diagnosed before 60 years of age) and 337 453 controls...

The clinical data for a patient with sick sinus syndrome was retrospectively analyzed. The patient was treated because of his heart palpitations and the increased chest pain. The patient admitted to the hospital under consideration for the left atrial tumor dependent on the echocardiography findings. After the CT scan and the dynamic ECG examination, the patient successfully underwent the left atrial tumor resection, atrial septal repair and cardiac pacing lead installation. The postoperative pathological diagnosis showed that the infective endocarditis and left atrial thrombus in left atrium was cured...

The cardiac Na(+) channel (Nav1.5) conducts a depolarizing inward Na(+) current that is responsible for the generation of the upstroke Phase 0 of the action potential. In heart tissue, changes in Na(+) currents can affect conduction velocity and impulse propagation. The cardiac Nav1.5 is also involved in determination of the action potential duration, since some channels may reopen during the plateau phase, generating a persistent or late inward current. Mutations of cardiac Nav1.5 can induce gain or loss of channel function because of an increased late current or a decrease of peak current, respectively...

In the past 10 years, large-scale genotyping has led to discoveries of sequence variants that confer the risk of many common and complex diseases. Due to pioneering work done, in large part, at deCODE genetics in Reykjavik, discoveries from Iceland have contributed substantially to key advances in population genetics. In cardiovascular medicine, a number of discoveries have been made, uncovering sequence variants that are associated with disorders such as coronary artery disease, atrial fibrillation, sick sinus syndrome, peripheral vascular disease, aortic aneurysm, and ischemic stroke...

Diseases such as the sick sinus and the Brugada syndrome are cardiac abnormalities, which can be caused by a number of genetic aberrances. Among them are mutations in HCN4, a gene, which encodes the hyperpolarization-activated, cyclic nucleotide-gated ion channel 4; this pacemaker channel is responsible for the spontaneous activity of the sinoatrial node. The present genetic screening of patients with suspected or diagnosed Brugada or sick sinus syndrome identified in 1 out of 62 samples the novel mutation V492F...

We investigated the mid-to-long-term results of transcatheter closure of atrial septal defect (ASD) in patients ≥40 years since there are issues with patients presenting with pulmonary hypertension and arrhythmia at the time of closure. In an 8.8 year period, transcatheter closure of ASD was successful in 179 patients aged ≥40 years, but failed in 2. Of the 179 patients (44 males, median 53 years), NYHA functional class, presence of arrhythmia and severity of pulmonary hypertension were compared before and after closure...

A 65-year-old man was scheduled for pacemaker implantation for symptomatic sick-sinus-syndrome (SSS). He suffered from multiple drug-allergies and allergies to several metals like quicksilver and titanium. Gold-coated pacemaker generators and polyurethane leads are effective in avoiding allergic reactions to pacing system components. Therefore, we decided to implant a custom-made gold-coated DDDR-pacemaker generator and polyurethane leads.

BACKGROUND: Familial sick sinus syndrome is associated with gene mutations and dysfunction of ion channels. In contrast, degenerative fibrosis of the sinus node tissue plays an important role in the pathogenesis of acquired sick sinus syndrome. There is a close relationship between transforming growth factor-β1 mediated cardiac fibrosis and acquired arrhythmia. It is of interest to examine whether transforming growth factor-β1 is involved in the pathogenesis of acquired sick sinus syndrome...

Pacemaker activity of the sino-atrial node generates the heart rate. Disease of the sinus node and impairment of atrioventricular conduction induce an excessively low ventricular rate (bradycardia), which cannot meet the needs of the organism. Bradycardia accounts for about half of the total workload of clinical cardiologists. The 'sick sinus' syndrome (SSS) is characterized by sinus bradycardia and periods of intermittent atrial fibrillation. Several genetic or acquired risk factors or pathologies can lead to SSS...

We report two young patients with symptomatic sick sinus syndrome admitted for permanent pacemaker implantation (PPI). On evaluation with echocardiography, one of them was found to have persistent left superior vena cava and venography showed absent right superior vena cava also. He underwent PPI with leads inserted via left superior vena cava, coronary sinus, right atrium and right ventricle. The other patient was incidentally found to have interrupted inferior vena cava with azygos continuation while being planned for temporary pacemaker implantation...

INTRODUCTION: To evaluate the clinical presentation, diagnosis, treatment, and outcomes of a group of dogs with sinoatrial node abnormalities. ANIMALS: Ninety-three client-owned dogs at a referral institution. MATERIALS AND METHODS: Medical records were reviewed for clinical history, diagnostic testing, and medical or permanent artificial pacemaker (PAP) treatment. Owners or veterinarians were contacted for long-term follow-up. RESULTS: Sixty-one dogs were symptomatic for their bradyarrhythmia and were diagnosed with sick sinus syndrome (SSS)...